ANALYSIS OF THE STRUCTURAL PROTEIN GENE SEQUENCE SHOWS KYASANUR-FOREST-DISEASE VIRUS AS A DISTINCT MEMBER IN THE TICK-BORNE ENCEPHALITIS-VIRUS SEROCOMPLEX
K. Venugopal et al., ANALYSIS OF THE STRUCTURAL PROTEIN GENE SEQUENCE SHOWS KYASANUR-FOREST-DISEASE VIRUS AS A DISTINCT MEMBER IN THE TICK-BORNE ENCEPHALITIS-VIRUS SEROCOMPLEX, Journal of General Virology, 75, 1994, pp. 227-232
Kyasanur Forest disease (KFD) virus is a highly pathogenic member of t
he family Flaviviridae producing a haemorrhagic disease in infected hu
man beings. Despite this high pathogenicity and potential epidemiologi
cal importance, there have been relatively few detailed antigenic or m
olecular studies on KFD virus. The nucleotide sequences of the genes e
ncoding the structural proteins of the virus have now been determined.
From these data we conclude that KFD virus is a distinct member in th
e tick-borne flavivirus complex with characteristic protease cleavage
sites, fusion peptide, signal sequences and hydrophobic transmembrane
domains. Comparison of the deduced amino acid sequences of KFD virus s
howed close relationships with other tick-borne flaviviruses. Among th
e structural proteins, the E protein showed maximum similarity (77.4 %
to 81.3 %) to tick-borne flaviviruses. Alignment of the amino acid se
quence with those of other known tick-borne flaviviruses revealed many
conserved regions confirming its identity as a member of the tick-bor
ne encephalitis group, although the genetic marker EHLPTA showed a T -
-> K substitution in KFD virus. The proposed genetic marker at amino a
cid positions 232 to 234 (AQE) was unique for KFD virus. A dendrogram
derived from the amino acid alignment showed a phylogenetic relationsh
ip similar to those obtained on the basis of serological studies. The
question of the sudden emergence of KFD virus in India and the possibi
lities of developing recombinant virus vaccines are discussed.